Plug for co-axial cables



June 24, 1969 w BQWLEY ET AL PLUG FOR CO-AXIAL CABLES Filed Feb. 16, 1967 F/GZ.

INVENTORS v n WNW R0 5mm W n W nwc 0 m U.S. 'Cl. 339-177 3 Claims ABSTRACT OF THE DISCLOSURE Plug for a co-axial cable comprising a metal shell in which a contact pin is located, the shell being assembled with a hollow body of insulating material and secured in assembly by a metal sleeve provided with apertures into which projections on the hollow body are adapted to snap.

This invention relates to plugs for connection to coaxial cables of the kind used in an electronic apparatus.

According to the present invention, the plug comprises a metal shell in which is supported a member of insulating material provided with a metal contact pin extending axially outwardly of the sleeve, a hollow body of insulating material extending axially of the shell from the opposite end of the pin and being secured thereto by an annular resilient metal sleeve provided with inwardly extending means engaging the shell, the sleeve also being provided with apertures into which projections on the outer face of the hollow body extend, the inner core of the co-axial cable being adapted to be attached to the contact pin and the outer braiding of the cable being adapted to be connected to the metal shell.

To enable the invention to be fully understood, it Will now be described, by way of example, with reference to the accompanying drawings in which:

FIGURE 1 is a side view of a plug according to one embodiment of the invention;

FIGURE 2 is a view similar to FIGURE 1 but partly in section;

FIGURE 3 is an end view of the plug;

FIGURE 4 is a sectional side view of the sub-assembly including the contact pin and shell;

FIGURE 5 is a sectional side view of the resilient sleeve; and

FIGURE 6 is an end view of the hollow body of insulating material.

As illustrated in the drawings, the plug comprises a metal shell 1 in which is mounted a cylindrical body 2 of insulating material to which a metal contact pin 3 is secured so as to extend axially of the shell and project axially outwardly of the open end thereof. The shell is formed with a hollow extension 4 which projects into the adjacent end of a hollow body 5 formed of synthetic plastics or other suitable electrically insulating material which is adapted to form a finger grip for the plug.

As shown more particularly in FIGURE 4, the shell includes a generally cylindrical portion formed with axial slots dividing this portion into a plurality of fingers 1a. In the embodiment illustrated, four such fingers are provided.

The hollow body or finger grip 5 is adapted to be assembled with the end of the shell remote from the contact pin 3, and the body and shell are detachably secured to one another by a resilient sleeve 6 which, as shown, is formed of metal rolled into the form of a tube having a longitudinally extending slit so that the sleeve will be radially expandible.

nited States Patent 0 3,452,323 Patented June 24, 1969 Portions of the sleeve are cut and bent to form inwardly projecting lugs 7 and spaced axially of the lugs the sleeve is cut to form windows or apertures 8.

The sleeve is adapted to be assembled with thepin and shell assembly illustrated in FIGURE 4 by sliding the fingers 1a inwardly of the sleeve with the lugs 7 aligned with the gaps between the fingers so that the lugs extend between adjacent fingers and abut the pin supporting member 2.

The hollow body 5 is then inserted axially into the end of the sleeve remote from the pin to snap opposed projections 9, formed on the outer face of the body 5, into opposed apertures or windows 8. It will be noted from FIGURE 2 that when the parts are assembled, the end of the body 5 adjacent the projections 9 frictionally engages the annular portion of the extension 4 of the shell which is disposed inwardly of the hollow body 5.

The diameter of the sleeve 6 before assembly with the body 5 is preferably slightly less than the outer diameter of the part of the hollow body 5 over which the sleeve fits, the provision of the axial slit in the sleeve will, however, enable it to be expanded radially to permit the insertion of the end of the hollow body and when so inserted the sleeve will frictionally engage the hollow body.

The finger grip can be detached when required by expanding the sleeve by the use of a suitable tool to release the projections 9 from the apertures 8.

When the parts are in assembly, the sides of the projections 9 will, by abutment with the opposed side edges of the apertures 8, prevent unintentional rotational of the hollow body 5 relative to the shell.

If desired, however, the projections 9 may be formed with rounded edges as indicated by 9a in FIGURE 6 so that by a deliberate rotation of the hollow body or finger grip the rounded portions will enable the projections to ride under the side edges of the apertures 8 to enable the sleeve to be removed. While the rounding of the edges will assist in the detachment of the sleeve when required, the radius of the rounded edges will preferably be such that relative rotation of the finger grip and sleeve in normal use is prevented and that the riding under of the edges referred to above is only effected by exerting a deliberate predetermined and fairly substantial rotational movement to the sleeve.

In use, the end of the coaxial cable is adapted to be inserted through the opening 5a in the hollow body 5. The end of the cable is bared and the central core inserted into the contact pin 3 and secured as by soldering and the outer braiding of the cable secured as by soldering to the extension 4 of the shell.

We claim:

1. An electrical plug for a co-axial cable having an inner core and an outer braiding, the plug comprising a metal shell, a member of insulating material within said shell and a metal contact pin on said member and extending axially outwardly of the shell, a hollow body of insulating material extending axially of the shell from the opposite end to said pin, an annular resilient metal sleeve housing said shell, integral resilient lugs on said sleeve engaging said member within said shell, said lugs extending inwardly of the shell and abutting the contact carrying member, the sleeve also being formed with apertures and projections being provided on the hollow body and snapped into said apertures, the inner core of a coaxial cable being adapted to be attached to the said contact pin and the outer braiding of the cable being adapted to be connected to the metal shell.

2. An electrical plug according to claim 1, wherein projections are formed integrally with the hollow body at circumferentially spaced intervals, each projection en- 3,452,323 l p V gaging in a said aperture in the sleeve, the projections being References Cited drawn into abutment with an edge of its aperture by the resilient abutment of the lugs against the contact pin UNITED STATES PATENTS carrying ng nben I I Kenney 3. An electrical plug according to' claim 2, wherein the shell comprises a generally cylindrical metal member 5 FOREIGN PATENTS provided with a plurality of integral axially extending 853,459 11/1960 Great Britain.

fingers, the lugs on the sleeve being positioned in slots between adjacent fingers of the shell. MARVIN A. CHAMPION, Primary Examiner. 

